ISDs Chp 12 pg 36

Can someone help me with how the expected no of the zx are being calculated?

 

See pg.no.33 Step 3 ...... 0.02*20=0.4, 0.14*20=2.8 so on.
You can check out from tables for.......... .02088*20=0.4176 , 0.13591*20=2.7182 so on.

 

What are you using from tables?

 

see pg.no. 160&161 of tables......
P(0<Z<1)=P(Z<1)-P(Z<0)=0.84134-0.5=0.34134 it shows that 34.134% of the normal data is in the range [0,1] for simplicity 0.34 is written in notes.

PS: hope you know how to get Probabilities from tables.

 

Thank you